Washout Periods in Inflammatory Bowel Disease Trials: A Systematic Literature Review and Proposed Solutions.

Inflammatory bowel diseases (IBD), encompassing ulcerative colitis (UC) and Crohn's disease (CD), impose a substantial burden. Despite many effective molecules, significant numbers of patients do not achieve clinical remission at 1 year1 and undergo surgery during their lives, revealing an important unmet need and therapeutic gap. Multiple randomized controlled trials (RCTs) are ongoing or planned to develop more effective and tolerable therapies. In parallel, a dramatic decline in recruitment rates has been observed. A multitude of factors have contributed to poor recruitment rates, including a long washout period between the investigational drug and prior advanced therapies (ie, biologic or small molecule drug).2,3 This study aims to review the different washout periods with prior advanced therapies or immunosuppressants in phase 3 RCTs for UC and CD and to propose potential solutions to ultimately improve the design of clinical studies and patient enrollment in future trials.

Role of adherent and invasive Escherichia coli in Crohn's disease: lessons from the postoperative recurrence model.

OBJECTIVE: We used the postoperative recurrence model to better understand the role of adherent and invasive Escherichia coli (AIEC) bacteria in Crohn's disease (CD), taking advantage of a well-characterised postoperative cohort. DESIGN: From a prospective, multicentre cohort of operated patients with CD, AIEC identification was performed within the surgical specimen (M0) (N=181 patients) and the neoterminal ileum (n=119 patients/181) during colonoscopy performed 6 months after surgery (M6). Endoscopic postoperative recurrence was graded using Rutgeerts' index. The mucosa-associated microbiota was analysed by 16S sequencing at M0 and M6. Relative risks or ORs were adjusted on potential confounders. RESULTS: AIEC prevalence was twofold higher within the neoterminal ileum at M6 (30.3%) than within the surgical specimen (14.9%) (p<0.001). AIEC within the neoterminal ileum at M6 was associated with higher rate of early ileal lesions (i1) (41.6% vs 17.1%; aRR 3.49 (95% CI 1.01 to 12.04), p=0.048) or ileal lesions (i2b+i3) (38.2% vs 17.1%; aRR 3.45 (95% CI 1.06 to 11.30), p=0.040) compared with no lesion (i0). AIEC within the surgical specimen was predictive of higher risk of i2b-endoscopic postoperative recurrence (POR) (aOR 2.54 (95% CI 1.01 to 6.44), p=0.049) and severe endoscopic POR (aOR 3.36 (95% CI 1.25 to 9.06), p=0.017). While only 5.0% (6/119) of the patients were AIEC-positive at both M0 and M6, 43.7% (52/119), patients with history of positive test for AIEC (M0 or M6) had higher risk of ileal endoscopic POR (aOR 2.32 (95% CI 1.01 to 5.39), p=0.048)), i2b-endoscopic postoperative recurrence (aOR 2.41 (95% CI 1.01 to 5.74); p=0.048) and severe endoscopic postoperative (aOR=3.84 (95% CI 1.32 to 11.18), p=0.013). AIEC colonisation was associated with a specific microbiota signature including increased abundance of Ruminococcus gnavus. CONCLUSION: Based on the postoperative recurrence model, our data support the idea that AIEC are involved in the early steps of ileal CD. TRIAL REGISTRATION NUMBER: NCT03458195.

Effectiveness of Switching From Intravenous to Subcutaneous Infliximab in Patients With Inflammatory Bowel Diseases: the REMSWITCH Study.

BACKGROUND AND AIMS: We assessed the effectiveness of switching from intravenous to subcutaneous infliximab in patients with inflammatory bowel diseases (IBDs) treated with or without intensified intravenous regimen. METHODS: In this multicenter observational study, IBD patients in clinical remission (partial Mayo score ≤2 or Harvey-Bradshaw index ≤4) were switched to a unique dose of subcutaneous infliximab (120 mg every other week). Pharmacological and biological data were collected at baseline, visit 1 (4-8 weeks postswitch), visit 2 (8-16 weeks postswitch), and visit 3 (16-24 weeks postswitch). Relapse was defined as clinical relapse or fecal calprotectin increase ≥150 µg/g compared with baseline. RESULTS: Among 184 eligible patients, 72.3% (n = 133 of 184) agreed to switch to subcutaneous infliximab. At visit 3, a relapse occurred in 10.2% (n = 6 of 59), 7.3% (n = 3 of 38), 16.7% (n = 3 of 18), and 66.7% (n = 10 of 15) (P < .001) of patients receiving 5 mg/kg every 8 weeks, 10 mg/kg every 8 weeks, 10 mg/kg every 6 weeks, and 10 mg/kg every 4 weeks, respectively. Dose escalation to 240 mg every other week led to recapture clinical remission in 93.3% (n = 14 of 15). Infliximab serum levels increased after the switch (P < .0001) except for patients receiving 10 mg/kg every 4 weeks. In multivariable analysis, 10 mg/kg every 4 weeks regimen (odds ratio, 12.4; 95% confidence interval, 1.6-98.4; P = .017) and fecal calprotectin >250 µg/g at baseline (odds ratio, 5.4; 95% confidence interval, 1.1-27.6; P = .042) had a higher risk of relapse as well as reduced (41.7%) or stable (36.8%) infliximab serum levels between baseline and visit 1 compared with increased serum levels (12.7%) (P = .020 and P = .019, respectively). Patients' acceptability (10-point scale) was improved by the switch (6.9 ± 1.6 vs 8.6 ± 1.4; P < .0001). No severe adverse event was reported. CONCLUSIONS: Switching from intravenous to subcutaneous infliximab 120 mg every other week is safe and well accepted, leading to a low risk of relapse in IBD patients except for those receiving 10 mg/kg every 4 weeks requiring 240 mg every other week.

Natural History of Anal Ulcerations in Pediatric-Onset Crohn's Disease: Long-Term Follow-Up of a Population-Based Study.

INTRODUCTION: Anal ulcerations are frequently observed in Crohn's disease (CD). However, their natural history remains poorly known, especially in pediatric-onset CD. METHODS: All patients with a diagnosis of CD before the age of 17 years between 1988 and 2011 within the population-based registry EPIMAD were followed retrospectively until 2013. At diagnosis and during follow-up, the clinical and therapeutic features of perianal disease were recorded. An adjusted time-dependent Cox model was used to evaluate the risk of evolution of anal ulcerations toward suppurative lesions. RESULTS: Among the 1,005 included patients (females, 450 [44.8%]; median age at diagnosis 14.4 years [interquartile range 12.0-16.1]), 257 (25.6%) had an anal ulceration at diagnosis. Cumulative incidence of anal ulceration at 5 and 10 years from diagnosis was 38.4% (95% confidence interval [CI] 35.2-41.4) and 44.0% (95% CI 40.5-47.2), respectively. In multivariable analysis, the presence of extraintestinal manifestations (hazard ratio [HR] 1.46, 95% CI 1.19-1.80, P = 0.0003) and upper digestive location (HR 1.51, 95% CI 1.23-1.86, P < 0.0001) at diagnosis were associated with the occurrence of anal ulceration. Conversely, ileal location (L1) was associated with a lower risk of anal ulceration (L2 vs L1 HR 1.51, 95% CI 1.11-2.06, P = 0.0087; L3 vs L1 HR 1.42, 95% CI 1.08-1.85, P = 0.0116). The risk of fistulizing perianal CD (pCD) was doubled in patients with a history of anal ulceration (HR 2.00, 95% CI 1.45-2.74, P < 0.0001). Among the 352 patients with at least 1 episode of anal ulceration without history of fistulizing pCD, 82 (23.3%) developed fistulizing pCD after a median follow-up of 5.7 years (interquartile range 2.8-10.6). In these patients with anal ulceration, the diagnostic period (pre vs biologic era), exposure to immunosuppressants, and/or anti-tumor necrosis factor did not influence the risk of secondary anoperineal suppuration. DISCUSSION: Anal ulceration is frequent in pediatric-onset CD, with nearly half of patients presenting with at least 1 episode after 10 years of evolution. Fistulizing pCD is twice as frequent in patients with present or past anal ulceration.

New Therapeutic Strategies Are Associated With a Significant Decrease in Colectomy Rate in Pediatric Ulcerative Colitis.

INTRODUCTION: We evaluated the impact of immunosuppressants (IS) and antitumor necrosis factor (TNF) introduction on long-term outcomes of ulcerative colitis (UC) in a large population-based pediatric-onset cohort. METHODS: All patients included in the EPIMAD registry with a diagnosis of UC made before the age of 17 years between 1988 and 2011 were followed up retrospectively until 2013. Medication exposure and disease outcomes were compared between 3 diagnostic periods: 1988 to 1993 (period [P] 1; pre-IS era), 1994 to 2000 (P2; pre-anti-TNF era), and 2001 to 2011 (P3; anti-TNF era). RESULTS: A total of 337 patients (female, 57%) diagnosed with UC were followed up during a median duration of 7.2 years (interquartile range 3.8-13.0). The IS and anti-TNF exposure rates at 5 years increased over time from 7.8% (P1) to 63.8% (P3) and from 0% (P1) to 37.2% (P3), respectively. In parallel, the risk of colectomy at 5 years decreased significantly over time (P1, 17%; P2, 19%; and P3, 9%; P = 0.045, P -trend = 0.027) and between the pre-anti-TNF era (P1 + P2, 18%) and the anti-TNF era (P3, 9%) ( P = 0.013). The risk of disease extension at 5 years remained stable over time (P1, 36%, P2, 32%, and P3, 34%; P = 0.31, P -trend = 0.52) and between the pre-anti-TNF era (P1 + P2, 34%) and the anti-TNF era (P3, 34%) ( P = 0.92). The risk of flare-related hospitalization at 5 years significantly increased over time (P1, 16%; P2, 27%; P3, 42%; P = 0.0012, P -trend = 0.0006) and between the pre-anti-TNF era (P1 + P2, 23%) and the anti-TNF era (P3, 42%) ( P = 0.0004). DISCUSSION: In parallel with the increased use of IS and anti-TNF, an important decline in the risk of colectomy in pediatric-onset UC was observed at the population level.

New Therapeutic Strategies Have Changed the Natural History of Pediatric Crohn's Disease: A Two-Decade Population-Based Study.

BACKGROUND & AIMS: We evaluated the impact of immunosuppressants (IS) and anti-tumor necrosis factor (TNF) introduction on Crohn's disease (CD) long-term outcomes in a large population-based, pediatric-onset cohort. METHODS: All patients included in the EPIMAD registry with a diagnosis of CD occurring when they were younger than age 17 years and between 1988 and 2011 were followed up retrospectively until 2013. Three diagnostic periods were defined: 1988 to 1993 (period [P]1; pre-IS era), 1994 to 2000 (P2; pre-anti-TNF era), and 2001 to 2011 (P3; anti-TNF era). Medication exposure and disease outcomes were compared between the 3 diagnostic periods. RESULTS: A total of 1007 patients diagnosed with CD were followed up for a median duration of 8.8 years (interquartile range, 4.6-14.2 y). The IS and anti-TNF exposure rate at 5 years increased over time from 33.9% (in P1) to 76.5% (in P3) and from 0% (in P1) to 50.5% (in P3), respectively. In parallel, the risk for intestinal resection at 5 years decreased significantly over time (P1, 35%; P2, 31%; and P3, 22%; P = .0003, Ptrend < .0001), and between the pre-anti-TNF era (P1 + P2, 32%) and the anti-TNF era (P3, 22%) (P = .0007). The risk for progression from inflammatory to stricturing behavior decreased significantly over time (P1, 27%; P2, 28%; and P3, 20%; P = .11, Ptrend = .041) and between the pre-anti-TNF era (P1 + P2, 28%) and the anti-TNF era (P3, 20%) (P = .040). The risk for a CD flare-related hospitalization at 5 years remained stable over time (P1, 31%; P2, 31%; and P3, 29%; P = .76, Ptrend = .53). CONCLUSIONS: In parallel with the increased use of IS and anti-TNF, positive changes in the natural history of pediatric-onset CD were observed at the population level. A decreased risk of both intestinal resections and stricturing complications were observed during the anti-TNF era.

Ustekinumab Serum Trough Levels May Identify Suboptimal Responders to Ustekinumab in Crohn's Disease.

INTRODUCTION: The aim of this study was to evaluate the association between serum ustekinumab (UST) trough levels and response to induction and maintenance UST treatment in refractory Crohn's Disease (CD) patients. METHODS: We performed a prospective study including CD patients who received UST from September 2015 to January 2017. Patients received 90 mg of UST subcutaneously at weeks 0, 4, and 12, then every 8 weeks. Two cohorts of patients were analyzed: an induction cohort and a maintenance cohort. We evaluated clinical, biological, and imaging/endoscopic response to UST treatment. UST trough levels and anti-UST antibodies were dosed at weeks 12 and 28 in the induction cohort, and at a single time point in the maintenance cohort. RESULTS: Forty-nine patients were enrolled in the maintenance cohort. Mean concentrations of UST were 1.88 ± 1.40 µg/mL. UST trough levels were not significantly different in patients with or without clinical, biological, or imaging/endoscopic responses to UST treatment (p > 0.11). Twenty-three consecutive patients were included in the induction cohort. At week 12, mean UST concentrations were 1.45 ± 1.15 µg/mL. Patients with a biological response to UST treatment had significant higher serum UST trough concentration (median 1.72 µg/mL) than non-responders (median 0.56 µg/mL, p = 0.02). A UST trough level ≥ 1.10 µg/mL at week 12 was associated with a biological response to UST treatment at 6 months. CONCLUSION: UST trough levels were associated with a biological response at the end of the induction phase. In patients with low levels of UST, optimization treatment may be necessary to obtain a sustained response.

Radiological Response Is Associated with Better Outcomes and Should Be Considered a Therapeutic Target in Crohn's Disease.

BACKGROUND: The aim of the study was to identify factors associated with a radiological response and to assess the impact of radiological improvement in long-term outcomes in small bowel (SB) Crohn's disease (CD) patients. METHODS: We performed a retrospective study from June 2011 to June 2017 in the tertiary center, Claude Huriez Hospital in Lille, France. All SB CD patients, who underwent two magnetic resonance enterographies (MRE) 3-12 months apart, with at least 1-year follow-up after the second MRE, were included. Signs of radiological inflammation were identified by two expert radiologists in CD. Patients were classified as radiological responders (RR) and non-responders (NR). Hospitalization rates, adjustment of treatment, and surgical or endoscopic interventions were assessed and compared between RR and NR. Factors associated with a radiological response were also studied using the Cox model. RESULTS: One hundred and fifteen SB CD patients were included with a median follow-up of 17 months (IQR 11.6-28.3). There were 54 (47%) RR and 61 (53%) NR. The risk of surgical or endoscopic intervention was higher in NR than RR (p = 0.04), and the median delay until a surgical or endoscopic intervention was shorter in NR (p = 0.04). Multifocal disease, a hypersignal on diffusion-weighted or dynamic contrast-enhanced imaging, a stricture, or a fistula was significantly associated with a decreased probability of a radiological response (p < 0.05). CONCLUSION: This study shows that a radiological response is associated with a decreased risk of surgical or endoscopic intervention and should be considered as a therapeutic target in CD patients.

Subcutaneous Ustekinumab Provides Clinical Benefit for Two-Thirds of Patients With Crohn's Disease Refractory to Anti-Tumor Necrosis Factor Agents.

BACKGROUND & AIMS: Ustekinumab, a human monoclonal antibody against the p40 subunit of interleukins-12 and -23, is effective in inducing and maintaining remission in patients with luminal Crohn's disease (CD). We assessed the efficacy and safety of subcutaneous ustekinumab in patients with anti-tumor necrosis factor (anti-TNF) refractory CD. METHODS: We performed a retrospective observational study, collecting data from the Groupe d'Etude Thérapeutique des Affections Inflammatoires du tube Digestif on 122 consecutive patients with active CD refractory to anti-TNF therapy who received at least 1 subcutaneous injection of ustekinumab from March 2011 to December 2014, in 20 tertiary centers in Europe. Subjects were followed for at least 3 months. The primary outcome was clinical benefit, defined as reductions in symptoms and biochemical markers of CD and complete weaning from steroids, without surgery or immunosuppressant therapies. RESULTS: Seventy-nine patients (65%) had a clinical benefit within 3 months of receiving ustekinumab. Concomitant immunosuppressant therapy at study inclusion increased the odds for a clinical benefit from ustekinumab (odds ratio, 5.43; 95% confidence interval, 1.14-25.77; P = .03). Over a median follow-up period of 9.8 months (interquartile range, 5.3-14.5 months), the cumulative probabilities that patients maintained the clinical benefit for 6 and 12 months after introduction of ustekinumab were 93% and 68%, respectively. CONCLUSIONS: Almost two-thirds of patients with CD refractory to at least 1 anti-TNF agent receive clinical benefit from ustekinumab therapy, not requiring steroids for up to 12 months afterward. While awaiting results from ongoing trials, ustekinumab can be considered for use in these patients.

Ileal or Anastomotic Location of Lesions Does Not Impact Rate of Postoperative Recurrence in Crohn's Disease Patients Classified i2 on the Rutgeerts Score.

BACKGROUND: The Rutgeerts score with 5 grades of severity (i0-i4) is a suitable endoscopic model to predict clinical recurrence following ileocolonic resection in Crohn's disease (CD). Definition of grade i2 includes lesions confined to the ileocolonic anastomosis (i2a) or moderate lesions on the neo-terminal ileum (i2b). The aim of the present study was to evaluate the probability of clinical recurrence in i2a and i2b patients. METHODS: This multicenter retrospective study included all CD patients classified i2 at the first postoperative ileocolonoscopy. The primary outcome was to evaluate the probability of clinical recurrence in patients classified i2a and i2b. The secondary outcome was to compare the rate of global recurrence of CD. RESULTS: Fifty patients were included: 23 were classified i2a and 27 were classified i2b. The median duration of follow-up was 40 (18.0-80.4) months in the i2a group and 53.5 (25.0-69.0) months in the i2b group (p = 0.9). The probability of clinical recurrence was not significantly different between patients classified i2a and i2b (p = 0.64). Median time to clinical recurrence after the first ileocolonoscopy and probability of global CD recurrence were not different between the two groups (p ≥ 0.19). CONCLUSIONS: The rate of clinical postoperative recurrence is not different in i2a and i2b patients. These results suggest that the same therapeutic strategy should be used in all patients classified i2 on the Rutgeerts score whatever the location of postoperative CD recurrence.

Long-term effectiveness and safety of anti-TNF in pediatric-onset inflammatory bowel diseases: A population-based study.

BACKGROUND: Anti-TNF agents are the first biologic treatment option in inflammatory bowel disease (IBD). The long-term effectiveness of this strategy at the population level is poorly known, particularly in pediatric-onset IBD. METHODS: All patients diagnosed with Crohn's disease (CD) or ulcerative colitis (UC) before the age of 17 between 1988 and 2011 in the EPIMAD population-based registry were followed retrospectively until 2013. Among patients treated with anti-TNF, the cumulative probabilities of anti-TNF failure defined by primary failure, loss of response (LOR) or intolerance were evaluated. Factors associated with anti-TNF failure were investigated by a Cox model. RESULTS: Among a total of 1,007 patients with CD and 337 patients with UC, respectively 481 (48%) and 81 (24%) were treated with anti-TNF. Median age at anti-TNF initiation was 17.4 years (IQR, 15.1-20.9). Median duration of anti-TNF therapy was 20.4 months (IQR, 6.0-59.9). In CD, the probability of failure of 1st line anti-TNF at 1, 3 and 5 years was respectively 30.7%, 51.3% and 61.9% for infliximab and 25.9%, 49.3% and 57.7% for adalimumab (p = 0.740). In UC, the probability of failure of 1st line anti-TNF therapy was respectively 38.4%, 52.3% and 72.7% for infliximab and 12.5% for these 3 timepoints for adalimumab (p = 0.091). The risk of failure was maximal in the first year of treatment and LOR was the main reason for discontinuation. Female gender was associated with LOR (HR, 1.48; 95%CI 1.02-2.14) and with anti-TNF withdrawal for intolerance in CD (HR, 2.31; 95%CI 1.30-4.11) and disease duration (≥ 2 y vs. < 2 y) was associated with LOR in UC (HR, 0.37; 95%CI 0.15-0.94) in multivariate analysis. Sixty-three (13.5%) patients observed adverse events leading to termination of treatment (p = 0.57). No death, cancer or tuberculosis was observed while the patients were under anti-TNF treatment. CONCLUSION: In a population-based study of pediatric-onset IBD, about 60% in CD and 70% in UC experienced anti-TNF failure within 5 years. Loss of response account for around two-thirds of failure, both for CD and UC.

Histological healing induced by tofacitinib in ulcerative colitis: A multicentre study.

BACKGROUND: While the efficacy of tofacitinib to induce and maintain clinical and endoscopic remission is well established in ulcerative colitis (UC), little is known about its efficacy to induce histological remission. METHODS: We conducted a retrospective multicentric cohort study. UC patients ≥ 16 years treated by tofacitinib in whom histological activity has been evaluated before and after induction were eligible. The primary endpoint was the histological remission at the end of induction, assessed by the Nancy index and the epithelial neutrophilic infiltrate. RESULTS: A total of 42 patients with UC (93% previously exposed to an anti-TNF and 81% to vedolizumab) were included between July 2018 and April 2022 and were followed for a median duration of 84 weeks [IQR, 35-134]. At the end of induction period (whether prolonged or not), 19% and 24% of patients achieved histological remission, using the Nancy index and the epithelial neutrophilic infiltrate, respectively. Survival without tofacitinib discontinuation was significantly longer in patients without epithelial neutrophilic infiltrate at the end of induction (whether prolonged or not) compared with patients with epithelial neutrophilic infiltrate (p = 0.036). CONCLUSION: Tofacitinib induced histological remission in one fifth to one quarter of patients with UC who have previously failed anti-TNF or/and vedolizumab after induction (whether prolonged or not).

Changes Over Time in the Lémann Index and the Inflammatory Bowel Disease Disability Index in a Prospective Cohort of Patients With Crohn's Disease.

BACKGROUND: Crohn's disease (CD) is a progressive, destructive, and disabling disorder. Our study aimed to assess changes over time in the Lémann index (LI) and the Inflammatory Bowel Disease Disability Index (IBD-DI) in a cohort of CD patients. METHODS: This was a single-center prospective cohort study of 130 consecutive CD patients with a follow-up of at least 4 years. The LI 1 and the IBD-DI 1 questionnaires were assessed in 2016 and again between September 2020 and October 2021 (LI 2 and IBD-DI 2). RESULTS: Of the 130 patients with assessment of both LI 1 and IBD-DI 1, 61 had calculation of the LI 2 and 98 patients answered the IBD-DI 2 questionnaire, with a median time between the 2 evaluations of 4.2 years. The LI increased for 16 (26%), decreased for 26 (43%), and remained unchanged for 19 (31%) patients. The median LI did not change over time (9.6 vs 9.3; P = .14). Clinical disease activity was significantly associated with bowel damage progression. A high initial LI (>7.9) was not associated with CD progression (surgery, drug dose escalation, or change of biologic). The IBD-DI decreased for 59 (60.2%), increased for 37 (37.8%), and remained unchanged for 2 (2%) patients. The median IBD-DI decreased significantly over time (23.2 vs 21.4; P = .006). There was no correlation between the 2 indexes. CONCLUSIONS: This is the first prospective cohort study assessing changes over time in both the LI and the IBD-DI in CD patients. After 4 years, the LI appeared to be stable and the IBD-DI decreased, with no correlation between the 2 indexes.

After a long period of follow-up (4 years) of patients with Crohn's disease, bowel damages (assessed by the Lémann index) appeared stable and disability (assessed by the Inflammatory Bowel Disease Disability Index) decreased, without there being any correlation between the 2 indexes over time.

Etrasimod for the treatment of ulcerative colitis.

Sphingosine-1-phosphate (S1P) and its receptor (S1PR) are involved in the pathogenesis of multiple immune-mediated inflammatory disorders, including inflammatory bowel disease. The use of S1PR modulators represents a new therapeutic option for ulcerative colitis patients. Etrasimod is an oral selective S1PR1, S1PR4 and S1PR5 modulator that inhibits the trafficking of lymphocytes from the lymph nodes into the blood. Recently, etrasimod has demonstrated efficacy in the phase II OASIS study and its open-label extension for the treatment of ulcerative colitis patients. This article reviews the mechanism of action of etrasimod and summarizes the available clinical efficacy and safety data regarding etrasimod, which is a promising drug in the treatment of patients with moderate to severe ulcerative colitis.

Etrasimod is a new and promising drug for ulcerative colitis patients. Ulcerative colitis is a chronic inflammatory bowel disease caused by the body's inability to control its immune system. This leads to immune cell recruitment in the lining of the colon, causing inflammation. Etrasimod helps to control the level of immune cells in the blood, which means that fewer immune cells reach the lining of the colon, reducing inflammation. Etrasimod is fast-acting and given once a day by mouth and has demonstrated promising efficacy and safety in the phase II OASIS study and its open-label extension for the treatment of ulcerative colitis patients. Therefore, etrasimod may expand treatment options for patients with moderate to severe ulcerative colitis.

Promising phase II biologics for future Crohn's disease therapy.

INTRODUCTION: Although the physician's therapeutic arsenal of Crohn's Disease (CD) is rapidly expanded over the next 25 years, a significant proportion of patients remain non-responders, or develop a loss of response or intolerance to current therapies, indicating a need for new therapeutic strategies in CD. AREAS COVERED: This review examines the efficacy and safety data from phase II clinical trials on biologics, performed in patients with moderate-to-severe CD. A PubMed database literature review was conducted for relevant articles published from 2017 to 2022. Ongoing clinical phase II trials were retrieved from ClinicalTrials.gov database or abstracts from major congresses. Future perspectives for the treatment of CD patients with these new molecules were also discussed. EXPERT OPINION: Among the most promising biologics are interleukin (IL)-23p19 inhibitors (guselkumab, mirikizumab, and brazikumab), IL-6 inhibitors, and anti-adhesion molecules (ontamalimab). Furthermore, multiple biologics with different mechanisms of action are in clinical development for moderate-to-severe CD including molecules with anti-fibrotic mechanism of action (anti-TL1A, anti-IL-36 receptor). In addition to efficacy, some of them provide reassuring safety profiles. Phase III trials need to confirm these results, especially on their long-term safety issues.

Comparison of treatment effect between phase 2 and phase 3 trials in patients with inflammatory bowel disease.

BACKGROUND AND AIMS: The accumulation of multiple randomized controlled trials in the field of inflammatory bowel diseases provides an opportunity to compare treatment effects between phase 2 and 3 trials. We aimed to determine whether treatment effects observed in phase 3 investigating biologics and small molecule drugs differed from those in their preceding phase 2 trial. METHODS: We first performed a review of phase 2 and phase 3 trials enrolling ulcerative colitis (UC) or Crohn's disease (CD) patients. We compared the percent overall success for key endpoints between phases (several phase 3 could be matched to a single phase 2 trial). Then, we compared the percent overall success in the matched phase 2 and 3 trials (ratio 1:1), and performed sensitivity analysis. RESULTS: We identified 14 phase 2 (8 CD; 6 UC) and 24 phase 3 (13 CD; 11 UC) trials. In CD, the different analyses suggest that the percentage of overall success of clinical remission and clinical response was significantly higher in phase 2 than in phase 3 trials. In UC, the analyses suggest collectively that the percent of treatment effect seemed similar for clinical remission, clinical response and histologic outcomes between phases but with a lower percentage of overall success in phase 2 than in phase 3 trials for endoscopic endpoints. CONCLUSIONS: In UC, we observed a similar percentage of treatment effect for clinical and histologic outcomes between phase 2 and 3 trials but not for endoscopic outcomes. Whereas in CD, we showed a failure to reproduce similar results between phases. These results may help sponsors in the design of future drug development programs.

A Comparison of Treatment Effect Sizes in Matched Phase 2 and Phase 3 Trials of Advanced Therapeutics in Inflammatory Bowel Disease: Systematic Review and Meta-Analysis.

INTRODUCTION: Phase 2 trials are fundamental to the rational and efficient design of phase 3 trials. We aimed to determine the relationship of treatment effect size estimates from phase 2 and phase 3 clinical trials on advanced therapeutics in inflammatory bowel disease. METHODS: MEDLINE, EMBASE, CENTRAL, and the Cochrane library were searched from inception to December 19, 2022, to identify paired phase 2 and 3 placebo-controlled induction studies of advanced therapeutics for Crohn's disease (CD) and ulcerative colitis (UC). Treatment effect sizes were expressed as a risk ratio (RR) between the active arm and placebo arm. For the same therapeutics, RRs from phase 2 trials were divided by the RR from phase 3 trial to quantify the relationship of effect sizes between phases. RESULTS: Twenty-two studies (9 phase 2 trials, 13 phase 3 trials) were included for CD and 30 studies (12 phase 2 trials, 18 phase 3 trials) for UC. In UC (pooled RR 0.72; 95% confidence interval: 0.58-0.86; RR <1 indicates smaller treatment effect sizes in phase 2 trials), but not CD (pooled RR 1.01; 95% confidence interval: 0.84-1.18), phase 2 trials systematically underestimated treatment effect sizes for the primary endpoint compared with phase 3 trials. The underestimation was observed for clinical, but not endoscopic, endpoints in UC. DISCUSSION: Treatment effect sizes for the primary and clinical endpoints were similar across clinical trial phases in CD, but not UC, where only endoscopic endpoints were comparable. This will help inform clinical development plans and future trial design.